libxml2 in dessector - string encoding

Hi, I'm using libxml2 to read an xml-file (in utf-8) and set the tree-items in wireshark. My problem is that I only see unreadable text in wireshark. I used xmlNodeGetContent(node->xmlChildrenNode); to get the content and than proto_item_append_text(ti,ts); to set text text to a tree-item and I get something like ð§Derungsanhang What should I call to get a readable string?